Determination of a displacement of an Unmanned Aerial Vehicles (“UAVs”) is constantly needed for navigating and operating the UAVs. Currently-available technologies for measuring the displacement can only ensure performance and precision under certain conditions, such as within a certain height range. Moreover, the currently-available technologies are vulnerable to ambient interferences.
Among the currently-available technologies, a solution based on a monocular imaging device and an ultrasonic device can be limited by a detective distance of the ultrasonic device, therefore, normally only applicable within a low altitude of half meter to five meters. In addition, such monocular solution can also be vulnerable to noises existing in an ambient setting. An alternative solution that is based upon a binocular imaging device is limited by a length of a baseline between two lenses of the binocular imaging device and are only applicable within an altitude of one to ten meters. Another solution based on a Global Positioning Device (“GPS”) is not reliable under an indoor setting or under a complex ambient setting because of lack of reliable signal.
In view of the foregoing reasons, there is a need for a system and method for effectively and efficiently measuring the displacement of the mobile platform in wide range of heights.